Marry Me
by hyper13
Summary: Derek knows that Casey wants to get married. He also knows that Casey doesn't want to marry him. Inspired by the song by Thomas Rhett. Dasey, as always. One-shot.
1. Chapter 1

**Fifteen:** Casey McDonald wants to get married.

"I imagine something… big." Casey was saying, a dreamy tone to her voice. Derek slowed, stopping just before her door so she wouldn't see him but he could hear.

"Of course you do," Laughed Emily and Derek could almost picture her rolling her eyes. "I don't know. I think… I think I'd like something a little more subtle. Close friends and family."

"I think… in the end, it won't matter, as long as I'm getting married to the right person that I want to be with for the rest of my life." Casey sighed, and Derek felt something tight in his chest, a strange alien feeling. It propelled him forward, feeling the snark bubbling up from his stomach.

"As if anyone would be warped enough in the head to want to marry you." Casey's happy, dreamy look fell, blue eyes snapping in his direction bright and angry. But he could see the flash of hurt and insecurity there, too. He almost missed it, but it was there. "Besides, I doubt there's a guy on earth who could ever live up to your impossible standards and pretty sure interspecies marriage is illegal." Emily giggled. He winked. Casey scowled.

"Der _ek_." The feeling in his chest lessened. There it was, her voice yelling his name broken in half; obnoxious and irritating and yet, somehow he felt better. It wasn't something he wanted to dwell on.

"Besides, you'd probably trip and fall at your wedding with that many people." He added, turning on his heel to leave, "Klutzilla strikes again!" He continued as he descended the stairs, pretending the couldn't hear her yelling at him and the door slamming behind him. She'd spend the next hour or so ranting about how insensitive he is rather than talking about weddings and Mr. Right. Derek, pleased with a job well done, headed downstairs dropping into his recliner to watch the hockey game.

* * *

 **Sixteen:** Casey McDonald wants a big wedding with tulips and bridesmaids dresses of pale pink.

Fiona was getting married and, of course, Casey was making a big deal about making everything perfect. "I would hope someone would do the same for me when I get married." She snapped when Edwin mumbled something under his breath about Casey being neurotic. She was standing at the altar, fixing one of those dumb expensive flower pieces and for a second Derek could swear she was standing there, all in white with her face covered with a veil.

Suddenly he felt ill.

Where in the world had that come from? Her face had gone all swoony, "But I'll have tulips," she sighed. Edwin shook his head and disappeared.

Derek still felt sick to his stomach and was trying to blink away images of Casey in white. "You'd have to find a husband first," he laughed from his seat in what would later be the audience. "And we know no one can ever meet your ridiculously high standards." He pinched his fingers together and mimed popping a balloon in her direction. It was fitting, as she certainly looked deflated. "Seriously, just buy a cat and move on from the notion that you'll ever find someone to be with."

Angry tears welled in her eyes, and she adjusted the flowers once more before stomping away. Derek had been crueler than usual, but it had succeeded in wiping away the image of Wedding!Casey. Yuck.

It was unnerving how he felt worse than before. Maybe that's why he was found kissing Casey's cousin, Vicky, during the reception. It wasn't until they were standing next to one another, Casey looking angry and Vicky looking smug, that he realized they looked similar.

Jeez, now he was going to be sick.

* * *

 **Seventeen:** Casey McDonald wants to get married and have a live band playing music.

Derek watched, angrily, as a senior leaned against Casey's locker, making her laugh. Why was he angry? He had no clue. It must be that broth-gag, nope not that. Still, Kyle is way too old for Casey and Derek knows Kyle. He makes Derek look like the king of monogamy.

Casey would be impressed he even knew what that word meant.

But Casey was going to get hurt, and everyone at home was going to be suffering until she moved on. That's why he's angry, yeah, this Kyle guy doesn't know what he's doing. Derek waited until Kyle moved on from Casey's locker, looking over his shoulder to check her out. Derek fell into step beside him. "Careful with that one," he said, making a 'yeesh' face.

"What?"

"That chick," he jerked his thumb in Casey's direction. "Stage five clinger." He shook his head. "She's probably already planning your wedding now that you've talked to her."

"Yikes," Kyle said, making a face. "And I just wanted her to tutor me."

"You weren't hitting on her?"

"Well, I thought about it, but I definitely won't be now." He sighed. "I guess I'll have to find a new tutor, too."

"Yeah, absolutely." Derek agreed. It was better to be safe than sorry, right? Right.

* * *

 **Eighteen:** Casey McDonald wants to get married; she wants to have both her father and George walk her down the aisle.

"You did it!" Nora said excitedly to Casey, just as his dad wrapped his arms around Derek greeting him with the same words, though he sounded surprised by Derek's graduation. Honestly, so did Derek.

"I know!" Casey jumped up and down with her mom. "Part one of my life plan is complete. Graduate High School. Next graduate college, get a nice job, and then fall in love and get married." She sighed, happily and Derek froze.

There it was again, that word: _Marriage_.

"I think you getting married will be more surprising than the fact that I'm going to Queen's University in the fall." Their whole family looked at him with wide eyes. He only had eyes for Casey, however. She'd been waiting to announce where from the tons of schools she'd applied to, which she was going to attend. He'd known for weeks that she was picking Queen's-thank you, Edwin.

"I'm going to Queen's." She said looking like she was having trouble deciding whether she should be surprised he had gotten in or mad that he'd insulted her ability to get married, yet again.

How was this becoming a theme with them? Derek was distracted from his thoughts as Casey said some unkind words and Nora and his dad strangled him in hugs because "You're going to _college_."

"Don't sound so surprised, dad." Derek laughed.

"Why not? It certainly is a miracle." Casey snarked. She hadn't yet forgiven him for the marriage comment, but that was alright, because she hadn't changed where _she_ was going for university.

* * *

 **Twenty:** Casey McDonald wants to get married to someone who challenges her, who pushes her to be better, but loves her for who she is.

"Do you ever think about getting married?" Casey asked from the futon beneath his elevated bed.

"All the time," he said dryly. "Do you ever think about hanging out in _your_ dorm to do homework?"

"About as often as you think about getting married," Casey said, cheerily.

"Touche," he muttered, rolling onto his side.

"Seriously, though, how come you never want to try a real relationship? Don't you want something of substance."

"Oh, the girls I spend time with have substance." He wiggled his eyebrows in that way that annoys her, even though she couldn't see him.

"Stop making that face," she said, anyway, because she knows him. "I mean someone who understands you, who gets you, who challenges you to be better but still appreciates who you are." Did she understand she was describing herself? "Someone who might annoy the hell out of you, but you wouldn't have it any other way, and despite being as obnoxious as humanly possible to you, they'd always have your back."

Derek's throat felt tight, and his eyes stung. "You watch too many movies," he said, instead of the words swirling around in his brain: it's you, it has always been you.

"I want that," Casey ignored his quip.

"I know," he said.

* * *

 **Twenty-Five:** Casey McDonald wants a brunch menu for her catered wedding dinner.

It was Casey's birthday. She was having a karaoke party, of all things. It was awful, most of the singing was pretty terrible, but she was tipsy and having fun, and that was pretty great.

... Until Abel showed up.

Abel was Casey's too perfect, too neurotic boyfriend. Casey claimed that he got her, but none of the other claims she so passionately insisted was part of a good partnership six years ago. Still, Abel had stuck around two and a half years now.

"Alright, alright." the too tan boyfriend said, taking the mic from a tipsy Emily, who'd just given a shaky rendition of some pop song that, to Derek, sounded like all the other pop songs on the radio. He took a sip of his drink standing and leaned against the bar. Abel continued at the front of the room, "I want to take a minute to say happy birthday to the most beautiful woman in my life," Casey beamed and blushed beneath the praise and attention. "I hope you're having a great time?" He gestured her to his side.

"Yeah, I am." She laughed.

"Excited to see your family?" Abel smiled. Derek rolled his eyes.

"Yeah," she said, also rolling her eyes.

"One last question before I let the entertainment continue," Abel said, slowly going down on one knee. Casey's going to be so mad that her memory of this is even the slightest bit hazy. "Casey McDonald, will you marry me?"

There was a pause, which surprised Derek because all she seemed to talk about was how she wanted to get married; he expected she would have jumped up and down shrieking her yes. Her eyes met his, and he stared back, unwavering.

Casey broke the eye contact, first. "Yes." It was nothing like Derek had pictured she would answer that question, not that he'd thought about it… much.

* * *

 **Twenty-Six:** Casey McDonald wants to get married, but she doesn't want to marry Derek.

From their engagement, the wedding planning was a whirlwind. Until, suddenly, it wasn't. There was a lot of wedding talk in the months that followed Casey's twenty-sixth birthday, but he never heard a mention of a date. The whole thing was planned, but nothing booked.

"They haven't picked a date, yet," Edwin said, one day when Derek so casually mentioned it. "Casey hasn't decided what's the right date, yet."

"I'm still surprised Casey wants to get married at all," Sam said.

"What?" Derek sat up, surprised. Did Sam know something he didn't?

"Well, I would have thought she would find the whole tradition archaic and offensive to women or something."

"Oh," Derek sighed, leaning back in his chair. "Yeah, she wants to get married." But, she didn't want to marry him.

* * *

 **Twenty-Eight:** Casey McDonald is getting married.

Eventually, they did pick a date, but Derek got the feeling that there were a lot of fights around it until it happened. Even he didn't know why Casey was dragging her feet. The wedding day came, and Derek was there in the groom's dressing room, adjusting his tie. How he'd made it in the party was beyond him, and why he'd agreed to torture himself this way was not something he could answer.

Abel was panicking. "I don't even think she wants to get married," he was spouting off to the best man. Derek listened intently while adjusting his tie. "I've hardly seen her since we picked the date a month ago. She comes home late, leaves early; she's always working."

"Relax," the best man-Logan? Paul? Simon?-said, patting his friend on the shoulder. "She would have called it off by now if she didn't want to get married.

"Right, right."

"I've known Casey a long time," Derek spoke up. "She's always talked about getting married as long as I can remember, I'm sure she's not second-guessing the commitment." He could only hope she was second-guessing the who the commitment was to.

"Right," Abel smiled and breathed in and out in such a Casey fashion that Derek had to wonder how these two functioned together.

"I'll go check on her," he offered, realizing that she probably had her freak out and he'd have a better chance of calming her down.

"Thank you, Derek," Abel said, smiling tightly at Derek. He said nothing, leaving the room in search of Casey.

She was alone when he found her. Casey was staring into the mirror, taking deep breaths and apparently trying not to cry. He knew that face. "Case…" She jumped, whirling around.

"What are you doing?"

"I thought you might be freaking out right now."

"Why would you think that?"

"Because you always freak out when you do something big." She smiled, and he smiled.

"I don't think I want to do this, Derek."

"Of course you do." He said, "you've always wanted to get married."

"Yeah, I just pictured it so much differently."

"Really?" He looked around in surprise, "That dress looks like the one you used to drone on and on about to Emily. There are tulips everywhere, Dad and Dennis are waiting to take you down the aisle, the food smells great… Casey, you want to get married."

"Yeah, you're right." Of course he is; Casey McDonald wants to get married, she doesn't want to marry him.

"I know."

"It's just…" she hesitated, and Derek waited with bated breath.

"Casey, darling, time to go!" Maya declared, wandering into the room with a flourish. She blanched at seeing Derek, "places, Derek." She smiled, "I should have known you would be a troublemaker." He looked back to Casey, ignored Maya's instructions to move along.

"Case."

"Go ahead, Derek." She said giving him what he thought looked to be a sad smile. Right, he should have known better than to expect something to happen, here and now of all places. He left the room and then continued, rather than going to where he was supposed to, he pulled off his tie and headed off until he found himself sitting in a booth at Smelly Nellies.

He should never have gone to that wedding in the first place. Looking at the menu before him, Derek sighed. Maybe he should have gone to a bar, instead. Dropping his head down on the table, the missing groomsman groaned. He'd get so much shit for this and someone would be wanting an explanation. How long he spent there, he wasn't sure; it felt like an eternity, but it probably was only twenty minutes. His peace was disturbed, though, when he heard a shifting of fabric that caused him to raise his head up so he could stare at whoever had come to find him-his guess was Edwin-and potentially reprimand him for missing Casey's wedding.


	2. Chapter 2

"Hey, man scoot over." A vaguely familiar, male voice said. He hadn't realized it until he felt the crushing, sinking feeling in his chest that Derek had been hoping that Casey would be sliding into the booth next to him, and not an old classmate.

Especially not Truman.

Still, Derek budged over making barely enough room for Truman to make himself comfortable. "You're all dressed up." He commented, and Derek rolled his eyes.

"Yeah, just came from a wedding." Why hadn't he gone to a bar where he could order a drink, tip it back and ignore anyone trying to have a conversation with him?

"Oh, that's right. Casey was getting married today, right?"

Derek straightened, surprised that Truman knew this. "Yeah." Truman checked his watch. "How'd you know?" He didn't think that Casey, despite her penchant for remaining friends with ex-boyfriends, would have invited [i]Truman[/i] of all people to the wedding, but what did he know?

"Emily told me." Of course. "I thought the wedding was just starting, what are you doing here?"

Derek shook his head. "Weddings aren't really my thing. Too sappy for me." Truman looked like he was buying it, now if only he could convince himself. "I'm sure she only invited me out of courtesy, anyway, we're not exactly best friends, you know."

"Right," Truman said, and Derek thought maybe he wasn't buying it after all. "Whatever helps you sleep at night, dude."

"What's that supposed to mean?" Why was he getting sympathetic looks from [i]Truman French[/i]? He'd really hit a low point in his life. Truman pursed his lips, shaking his head and Derek dropped his head back onto the table. Everyone but Casey knew. Except, she had to see because she could be a little oblivious sometimes, but Casey McDonald wasn't dumb.

"Huh." A hand landed on Derek's back in what, he supposed, would be a comforting gesture. "Think you need to come to terms with your feelings really quick."

Derek sat up to say something, anything that would make the other guy go away but he was already rising from the table, staring out the window. He turned, and Casey was standing in her wedding dress in the parking lot. She made eye contact with Derek and put a hand to her mouth. God, he hated tears. Still, he practically shoved Truman out of the way to go and meet her outside. "Casey..." What was he supposed to say? He didn't want to jump to any conclusions. His heart thudded in his chest, and his stomach felt like he was taking a freefall, so maybe he'd already jumped to a conclusion, but he didn't want to hear something else.

Somehow he'd forced his feet to move forward so that he was standing directly in front of her and she shoved his shoulder. "Why didn't you say anything?"

"What?" Definitely not how he had expected the conversation to go.

Casey shoved him again. "You didn't say anything. I was about to get married and you. Didn't. Say. Anything."

"Uh, Casey, it's hardly my fault that you were going to get married. You said yes."

"Derek, if I had known..." She stopped, took a deep breath and wiped at the tears on her face. "If I'd known there was a chance, that you would..." She couldn't say the words, either. Couldn't be entirely sure.

"Known what," he breathed, and she just shook her head. "If you didn't know, why didn't you get married?"

"Can we drive somewhere?" He hesitated, nodded, and walked with Casey to his car. She climbed into the passenger seat, and him into the driver's seat but he didn't make a move to start the car. "I couldn't do it, I couldn't go through with marrying him. I thought it's what I wanted, I convinced myself that it was what I wanted but when it was time to go, I just... I couldn't. They were waiting for me, and Liz, I think she volunteered to come get me, but she just said, 'there's a taxi waiting out front. Go.' like she'd expected it would happen." Casey shook her head. "And Edwin, he came with her, and he-well, they both did-said that you..." Again, she was stopping herself from finding out the truth.

He turned to look back at her. "I should have said something," he agreed. Her face broke out into a tentative smile. "Casey, I love you. I have for a long time, and if [i]I[/i] had thought that I had even half a chance with you, I would have said something a long time ago, you never would have been with whats-his-face."

"Abel," she supplied, automatically and he shook his head. "Sorry."

"You were blind." He replied.

"You were dumb."

Tentatively, Derek reached out and grabbed her hand. She let him and then intertwined their fingers together, looking at him out of the side of her eyes. "You love me," she said, gleefully.

"Yeah," he said, letting out a breath as his shoulders felt lighter than they had in years. "And you..." he hesitated, and Casey smiled.

"I love you, too."

So, yes, Casey has always wanted to get married and, maybe, she'd wanted to marry him after all.


End file.
